Spray devices

Spray. For most purposes a simple spray device, based on the ordinary scent-spray, suffices. A finer and less intermittent spray can be obtained using the apparatus shown in Fig. 26. A narrow glass cylinder J has a ground-glass... 

The term nebulizer is used generally as a description for any spraying device, such as the hair spray mentioned above. It is normally applied to any means of forming an aerosol spray in which a volume of liquid is broken into a mist of vapor and small droplets and possibly even solid matter. There is a variety of nebulizer designs for transporting a solution of analyte in droplet form to a plasma torch in ICP/MS and to the inlet/ionization sources used in electrospray and mass spectrometry (ES/MS) and atmospheric-pressure chemical ionization and mass spectrometry (APCI/MS). 

The fluid dehvery in an air-spray system can be pressure or suction fed. In a pressure-fed system, the fluid is brought to the atomizer under positive pressure generated with an external pump, a gas pressure over the coating material in a tank, or an elevation head. In a suction system, the annular flow of air around the fluid tip generates sufficient vacuum to aspirate the coating material from a container through a fluid tube and into the air stream. In this case, the paint supply is normally located in a small cup attached to the spray device to keep the elevation differential and frictional pressure drop in the fluid-supply tube small. 

Oral 25, 50, 100 mg tablets Nasal 5, 20 mg unit dose spray devices... 

Figure 4 Schematic diagram of nasal spray devices.

The reactive mixture is heated to the necessary temperature in the spraying device (above the temperature at which the reaction starts), dispersed, and then applied to a surface in a uniform layer. The efficiency of the device depends on preserving the fluidity of the reactive mixture as it moves along the channel, preservation of the necessary degree of conversion of the reactive mixture at the exit from the nozzle for an adequate time, and sufficient dispersion of the jet leaving the nozzle of the sprayer. 

The spraying device works in the following way. The prepared liquid mixture of reactive components flows to channel 3 through pipeline 4, and is distributed in a circular direction by the rotation of core 2. This movement simultaneously reduces the apparent viscosity of the liquid. Then the liquid goes to the ring nozzle 5. Porous rings 6 and 7 are placed on the external and internal surfaces of nozzle 5 at a distance of (1 - 20)h from the exit (where h is the distance between the... 

Simple spray devices can deliver nasal formulations to the anterior portion of the nasal cavity. More sophisticated spray devices have been developed to deliver nasal formulations to the medial and posterior portions of the nasal cavity. 

Fig. 8.5. Schematic of an API interface for CEC—MS. 1, introduction of column effluent from CEC and spraying device 2, atmospheric pressure region 3, ion sampling aperture 4, atmospheric pressure to vacuum interface 5, skimmer 6, ion transfer optics (adapted from ref. [11]).

The hatch grate of the first section of tank 20 is loaded with superphosphate the spraying device is filled with water. Undissolved superphosphate and the solution flow into the first section. It is filled with water (to half of the space) and air (through a bubbler) to agitate the solution and dissolve the rest of the superphosphate. Then the solution is settled. The clarified solution is pumped into the second section of tank 20. The hatch grate of the second section is loaded with ammonia sulfate the spraying device is filled with water. 

A light increase of viscosity at higher pressures is disadvantageous for the break-up of drops, but inside the spraying device a mixture of liquid and C02 is formed. The diminished viscosity of this mixture dominates and as a consequence the diffusive mass transfer inside the droplet will be enhanced. 

Processes for the extraction of spray particles involving pressure nozzles and fluid assist spraying devices as well as different directions of mass transfer have been introduced. In a special high pressure apparatus, liquid solvents and dispersions with C02 can be extracted under high pressure. Relevant properties for the formation of drops are the viscosity of the liquid phase as well as the interfacial tension between the drop phase and the fluid phase. Results for oily and aqueous systems show a drop size distribution that is very suitable for the mass transfer. 

Fig. 8. Spray device for the preparation of calcium alginate microspheres...

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